1. Field of the Invention
The present invention generally relates to a socket connector for mounting a Central Processing Unit (CPU) module to a circuit board, and more particular to a pick-and-place device for the socket connector.
2. The Related Arts
A socket connector for mounting a Central Processing Unit (CPU) module to a circuit board comprises a rectangular base housing having a rectangular central opening and defining a number of cells arranged around the central opening. Conductive contact elements are received in the cells and have tails extending beyond the base housing for being soldered to the circuit board. A cover is movably supported on a top surface of the base housing and carries the CPU module thereon. The cover has a central opening substantially corresponding to the central opening of the base housing and a number of passages in registration with the cells. Pin legs depending from the CPU module are received in the passages and partially extend into the cells for physical engagement with the contact elements.
To properly position the socket connector on the circuit board, a pick-and-place device is employed to handle the socket connector. The pick-and-place device is attached to the socket connector in a releasable manner and has a flat surface for cooperating with a vacuum suction device. To accommodate the vacuum suction device, the flat surface must have a large area. An example is shown in a co-pending US patent application filed on Dec. 7, 2001, Ser. No. 10/031,381 which is assigned to the same assignee of the current application. The conventional pick-and-place device is conveniently made of synthetic materials that are insulation to heat. The conventional pick-and-place device comprises a board having a surface area covering all or most of the passages when the pick-and-place device is attached to the socket connector. The board must have a thickness sufficient to support the vacuum suction.
In carrying out soldering operations to attach the tails of the contact elements to the circuit board, a great amount of heat must be applied to and/or dissipated from the socket connector. Covering all or most of the passages by the conventional pick-and-place device is in general disadvantageous to heat transfer during the soldering operation.
Accordingly, an object of the present invention is to provide a pick-and-place device for a socket connector that allows excellent heat transfer in soldering operations.
Another object of the present invention is to provide a pick-and-place device allowing excellent heat transfer in soldering operations, while protecting the socket connector from contaminant occurring in the soldering operations.
To achieve the above objects, in accordance with the present invention, a pick-and-place device comprises a substantially rigid board having a bottom face positionable and releasably attachable to a surface of a socket connector in which a plurality of passages are defined. The rigid board covers a first group of the passages with a second group of the passages not covered by the board. Openings are defined in the board to expose some of the passages of the first group for enhancing heat transfer. A solid portion of the rigid board forms a top face of the board for vacuum handling purposes. A flexible, thin film has a first surface on which adhesive is coated for attaching the film to socket connector and covering both the passages of the second group and the exposed passages of the first group for shielding the passages against contaminants. The film partially overlaps and is adhesively attached to the top face of the board and has an opposite second surface exposed for vacuum handling of the socket connector. The film is thin and thus has no significantly adverse effect on heat transfer.